What is the Kangaroo Island koala management program?
Natural Resources Kangaroo Island (KI), together with the community, is aiming to maintain and enhance the state of valuable natural resources in the region. The KI koala management program began in 1997, following an independent assessment of the increasing koala population on the island and its impact on the vegetation, particularly manna gum. As a result, manna gum has been lost across many parts of the island and there are only small areas left that contain these preferred food trees, putting enormous pressure on the habitat. To date, there is no evidence to suggest that koalas can self-regulate their numbers, which means they may eventually consume all the available food within an area, resulting in their own starvation.
What is being done?
The KI koala management program is aiming to reduce koala densities to a sustainable level to conserve vegetation. The program is based on::
- koala fertility control (sterilisation)
restoration of koala breeding habitat (revegetation and protection of koala food trees)
monitoring (koala density and tree condition).
translocation of koalas from critically damaged natural areas on KI to South Australia’s South East region (the koalas' former natural range).
The program utilises non-lethal management options and involves no culling of koalas.
The South Australian Government is a signatory to the National Koala Conservation and Management Strategy 2009-2014, endorsed by the Natural Resources Management Council, which rejects culling or the spread of disease as management options for koalas.
What has been achieved?
Since the program began, more than 12,500 koalas have been sterilised and about 3,800 of these translocated to their historic range in the South East of South Australia, making it one of the largest fertility control programs in the world. In addition, koala numbers and tree condition are monitored annually to determine the effectiveness of the program and to inform management about where and when habitat restoration and koala management is required.
The program has been effective in reducing koala numbers through non-lethal measures, resulting in an improvement in tree condition in areas where management has been undertaken. Surveys are undertaken every five years - in 2010 the estimated population was 13,000 koalas, down from 27,000 in 2001.
Nevertheless, densities still remain above sustainable densities at 23% of monitoring sites. A sustainable population (roughly 0.75 koalas per hectare) is one at which it is predicted that damage to the eucalypt trees will be minimal.
Ongoing management of the koala population is critical to maintaining declining koala densities and ensuring the KI koala population does not begin to increase and reach their destructive, pre management numbers.